The present invention relates to a roller of a support arrangement for a rotary milking platform, wherein the support arrangement comprises a first rail member fixedly connected to the rotary platform, a second rail member stationarily arranged in a position below the platform, and a plurality of rollers arranged in a vertical space between the first rail member and the second rail member. The roller is one of said plurality of rollers, and comprises a peripheral contact surface to be in contact with the first rail member and the second rail member, and two side flanges arranged on opposite sides of the peripheral contact surface, wherein each side flange comprises a peripheral surface arranged at a longer radial distance from a rotation axis of the roller than the peripheral contact surface.
A support arrangement for a rotary milking platform has the tasks to support the platform, allow rotation of the platform, and maintain the platform in a position such that it rotates around a fixed centre vertical axis. The rollers support and allow rotation of the upper rail and the rotary platform on the lower stationary rail. Furthermore, the side flanges control the motion of the upper rail and the rotary platform in a horizontal plane such that the platform performs a rotary motion around a fixed vertical axis with a very good accuracy. Such a support arrangement may have a simple and reliable design.
However, certain rollers wear out faster than others, and it is desirable to be able to exchange individual rollers when they are worn out. However, it is difficult and time consuming to exchange the rollers in such a support arrangement. The upper rail and the lower rail prevent dismounting and mounting of the rollers in upward and downward vertical directions, and the side flanges prevent dismounting and mounting of the rollers in transverse directions. It is many times necessary to lift the platform and increase the vertical space between the rails for allowing exchange of the rollers. In practice, such a comprehensive measure is not performed for exchanging a few worn out rollers in the support arrangement. Instead, a part of one of the rail members is often cut out and welded back into place in order to allow exchange of a roller.